Pick and place machines (sometimes referred to as “PNP” machines) are commonly used during the manufacture of integrated circuit devices. Examples of integrated circuit devices that are commonly handled by pick and place machines during manufacture include Wafer Chip Scale Packages (sometimes referenced simply as “WCSP”) and plastic encapsulated integrated circuits.
In operation, a typical pick and place machine will pick up a part (e.g., an integrated circuit device or component thereof) and then place the part in a different relative location. To pick up a part, a contact mechanism, e.g., a vacuum tip, is first moved into contact with the part. If this contact is too forceful, it can damage the part. Such damage usually takes the form of small cracks on the silicon die which may later enlarge during heat cycling (e.g., soldering operations) and cause failure of the integrated circuit device. Similar impact damage can also occur during the pick and place machine placing operation. This internal damage may be completely invisible even with a careful microscopic visual inspection of the part.
Different integrated circuit devices exhibit different sensitivities to impact damage depending, for example, on the thickness of the device or component involved and other factors. As integrated circuit devices trend toward smaller and thinner packages, however, the problem of impact damage is seen to be increasing. Further, as manufacturing processes become faster, the opportunity for impact damage increases.